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Since wireless sensor networks are energy constrained, introducing a method that facilitates the efficient use of the available energy in each node is a fundamental design issue. In this work, a mechanism to monitor the residual energy of sensor networks is proposed. The information about the residual energy of each sensor node in the network is saved in a special node called monitoring node. This information can be used as input to other applications to prolong the network lifetime. Each sensor node in the network uses the proposed prediction-based model to forecast its energy consumption rate. The model's performance is measured based on the number of energy packets sent to the monitoring node for various thresholds (prediction errors). The simulation results showed that reducing the threshold will produce more accurate projection of the residual energy of each node in the monitoring node. However, as the threshold is further decreased the number of energy packets sent to the monitoring node grows significantly. This incurs higher energy map construction cost on the network in terms of energy and bandwidth. The simulation results also showed the tradeoff between increasing the accuracy of the prediction model and reducing the cost of energy map construction.

In this thesis, we develop an approach to characterizing the uncertainty in energy use toward development of a real-time intelligent energy monitoring system for an autonomous under- water vehicle (AUV). The purpose of the intelligent energy monitoring system is to estimate current energy onboard the AUV, estimate energy needed to complete a desired mission, and to determine if and when the AUV should terminate the current mission and return to the recovery location due low energy reserves. In this work, we examine the relationship between water currents and energy used by the AUV, and we specifically address ways to characterize the relationship between uncertainty in water currents and uncertainty in energy use. We also examine the development of a battery model for the AUV, and test this model under simulated and real world conditions. We also develop a model for predicting future energy states, and evaluate this model using real world trials. / Master of Science / In this thesis, we develop an approach to characterizing the uncertainty in energy use for an energy monitoring system for an autonomous underwater vehicle (AUV). The purpose of the energy monitoring system is to estimate current energy onboard the AUV, estimate energy needed to complete a desired mission, and to determine if and when the AUV should cancel the mission and return to the recovery location due low energy levels. In this work, we examine the relationship between water currents and energy used by the AUV, and we specifically address ways to characterize the relationship between uncertainty in water currents and uncertainty in energy use. We also examine the development of a battery model for the AUV, and test this model under simulated and real world conditions, and develop a model for predicting future energy levels.

The environmental and economic consequences of climate change are severe and are being exacerbated by increased global carbon emissions. In the United States, buildings account for over 40% of all domestic and 7.4% of all global CO2 emissions and therefore represent an important target for energy conservation initiatives. Even marginal energy savings across all buildings could have a profound effect on carbon emission mitigation. In order to realize the full potential of energy savings in the building sector, it is essential to maximize the energy efficiency of both buildings and the behavior of occupants who occupy them. In this vein, systems that collect and communicate building energy-use information to occupants (i.e. eco-feedback systems) have been demonstrated to motivate building occupants to significantly reduce overall building energy consumption. Furthermore, advancements in building sensor technologies and data processing capabilities have enabled the development of advanced eco-feedback systems that also allow building occupants to share energy-use data with one another and to collectively act to reduce energy consumption. In addition to monitoring building occupant energy-use, these systems are capable of collecting data about specific conservation actions taken by occupants and their interactions with different features of the eco-feedback system. However, despite recent advancements in eco-feedback and building sensor technologies, very few systems have been specifically designed to enable research on the effectiveness of different behavior-based energy conservation strategies in commercial buildings. Consequently, very little research has been conducted on how access to such systems impacts the energy-use behavior of building occupants. In this dissertation, I describe how my research over the past three years has advanced an understanding of how eco-feedback systems can impact the energy-use behavior of commercial building occupants. First, I present a novel eco-feedback system that I developed to connect building occupants over energy-use data and empower them to conserve energy while also collecting data that enables controlled studies to quantify the impacts of a wide variety of energy conservation strategies. Next, I present a commercial building study in which this eco-feedback system was used to investigate the effects of organizational network dynamics on the energy-use of individuals. I then introduce a new set of metrics based on individual energy-use data that enables the classification of individuals and building occupant networks based on their energy-use efficiency and predictability. I describe the principles behind the construction of these metrics and demonstrate how these quantitative measures can be used to increase the efficacy of behavior-based conservation campaigns by enabling targeted interventions. I conclude the dissertation with a discussion about the limitations of my research and the new research avenues that it has enabled. / Ph. D.

<p>Research on net-zero energy buildings (NZEBs) has been largely centered around improving building energy performance, while little attention has been given to indoor air quality. A critically important class of indoor air pollutants are nanoaerosols – airborne particulate matter smaller than 100 nm in size. Nanoaerosols penetrate deep into the human respiratory system and are associated with deleterious toxicological and human health outcomes. An important step towards improving indoor air quality in NZEBs is understanding how occupants, their activities, and building systems affect the emissions and fate of nanoaerosols. New developments in smart energy monitoring systems and smart thermostats offer a unique opportunity to track occupant activity patterns and the operational status of residential HVAC systems. In this study, we conducted a one-month field campaign in an occupied residential NZEB, the Purdue ReNEWW House, to explore how energy use profiles and smart thermostat data can be used to characterize indoor nanoaerosol dynamics. A Scanning Mobility Particle Sizer and Optical Particle Sizer were used to measure indoor aerosol concentrations and size distributions from 10 to 10,000 nm. AC current sensors were used to monitor electricity consumption of kitchen appliances (cooktop, oven, toaster, microwave, kitchen hood), the air handling unit (AHU), and the energy recovery ventilator (ERV). Two Ecobee smart thermostats informed the fractional amount of supply airflow directed to the basement and main floor. The nanoaerosol concentrations and energy use profiles were integrated with an aerosol physics-based material balance model to quantify nanoaerosol source and loss processes. Cooking activities were found to dominate the emissions of indoor nanoaerosols, often elevating indoor nanoaerosol concentrations beyond 10⁴ cm^-3. The emission rates for different cooking appliances varied from 10¹¹ h^-1 to 10¹⁴ h^-1. Loss rates were found to be significantly different between AHU/ERV off and on conditions, with median loss rates of 1.43 h^-1 to 3.68 h^-1, respectively. Probability density functions of the source and loss rates for different scenarios will be used in Monte Carlo simulations to predict indoor nanoaerosol concentrations in NZEBs using only energy consumption and smart thermostat data.</p>

Trends such as online shopping, fast pace of lifestyle and wellness issues are key drivers for consumers' preferences of shopping activities and product selection. There is evidence that food retail has shifted towards smaller in size stores and ready meals or food products which require less time for cooking. In fact, the frozen food market has increased recently and is projected to rise by 27% by 2020. This study focuses on energy efficiency of small size frozen food supermarkets. The investigation started with in-situ monitoring of energy use and environmental conditions in two frozen food stores with different HVAC but same refrigeration systems and store operation schedules. A dynamic thermal model of frozen food stores was developed using EnergyPlus and validated using the monitored data. The model takes into account interlinked heat exchanges between building, HVAC and refrigeration systems and was used to investigate energy efficiency improvements. Two HVAC systems were examined; coupling heating, air-conditioning and ventilation (coupled system) and separating heating and air-conditioning from ventilation (decoupled system). A number of refrigeration systems (remote, centralised, cascade, transcritical CO2 booster) and working fluids were investigated. Analysis of the monitored data has shown that energy use of frozen supermarkets is at the upper range of published supermarkets energy use benchmarks (1085 kWh/m2/annum). It was also shown that sales area temperature is highly affected by HVAC controls, refrigeration equipment and transient customers' pattern. The computational study has identified energy performance of sub-systems and their interactions. Results indicate that 61% of total energy use is due to the refrigeration system while HVAC and lighting are the next most energy intensive systems. Apart from lighting upgrade to LED which offers high energy savings (23%), energy efficiency can be improved for both coupled and decoupled HVAC systems by incorporating night ventilative cooling and operating remote LT cabinets with lower ambient temperature. Night ventilative cooling can lead to reduction of 3.6% in total energy use. Centralised refrigeration systems change the heating/cooling balance and can reduce the total energy use by up to 20% for a CO2 centralised system. The results of this research project are a contribution towards better understanding of energy use in food dominant supermarkets and their energy savings potential.

Este trabalho descreve os requisitos para definição, implantação, manutenção e melhoria de sistemas de gestão de energia no ambiente industrial com um enfoque sistemático no que se refere às rotinas de melhoria contínua para eficiência energética. Para tanto, propôs-se a estruturação de uma plataforma automatizada visando o monitoramento, verificação e gerenciamento de recursos energéticos compatível com um sistema de gestão de energia normatizado, incluindo os requisitos de uso e consumo de energia, além do monitoramento, documentação, comunicação, melhores práticas de projeto, aquisição de equipamentos, sistemas, processos e recursos humanos envolvidos no desempenho energético. A estratégia de análise do uso da energia proposta neste trabalho baseou-se na metodologia de monitoramento e gestão de índices que consiste em uma abordagem sistemática na utilização de recursos energéticos objetivando alcançar o melhor resultado econômico através da gestão permanente do consumo de energia. Além disso, propôs-se a inclusão dessa metodologia como um procedimento na fase de planejamento da norma ISO50001, a qual estabelece os conceitos para a implantação de sistemas de gestão de energia. Visando integrar as ferramentas associadas a este cenário, esta plataforma contempla o uso de um sistema de supervisão associado a um aplicativo (Soft-PLC) que executa a aplicação de controle do uso de energia em um ambiente industrial com automação distribuída compatível com a norma IEC61131. O projeto do aplicativo de controle do uso de energia foi conduzido adotando-se diferentes linguagens de programação definidas na IEC para executar todos os procedimentos de medição, monitoração e gestão exigidos pelo sistema, incluindo análise comparativa com as “melhores práticas”, uso de tecnologias inovadoras, abordagem de produto e serviço, auditoria energética e conformidade com marcos regulatórios. Os resultados decorrentes da adoção de uma plataforma baseada em automação para o gerenciamento energético incluem elevada flexibilidade, adaptabilidade e usabilidade do sistema. Além disso, um projeto de automação neste cenário de plataforma aberta tende a apresentar menores custos de desenvolvimento e implantação. / This work describes the requirements for the definition, implementation, maintenance and improvement of energy management systems in the industrial environment with a systematic approach concerning continuous improvement routines for energy efficiency. For this purpose, it was proposed the establishment of a framework based on automation to implement monitoring, verification and management of energy resources compatible with a standardized energy management system, including requirements for energy use and consumption, in addition to monitoring, documentation, communication, project best practices, equipment acquisition, systems, processes and human resources involved in energy performance. The strategy of energy use analysis proposed in this work is based on the methodology of monitoring and targeting that consists of a systematic approach in the use of energy resources in order to achieve the best economic result through the permanent management of energy consumption. Furthermore, this work includes that system as a procedure in the planning phase of ISO50001 standard which establishes the concepts for energy management systems implementation. In order to aggregate all tools associated to this scenario, this paper proposes the use of a supervisory tool integrated to a real-time software (Soft-PLC) that runs the control application and a factory floor distributed system automation hardware in an IEC61131 compatible environment. The project of the control application of energy use was conducted using different programming languages defined in IEC to perform all the procedures of measurement, monitoring and management required by the system, including comparative analysis with the "best practices", use of innovative technologies, product and service approach, energy audit and compliance with regulatory milestones. The expected results of adopting an automation-based platform for energetic management include system flexibility, adaptability and usability. Besides, a project of automation in this scenario of open platform tends to introduce lower development and deployment costs.

This thesis presents an energy monitoring system to measure energy consumption of software applications to support security and power management for embedded devices. The proposed system is composed of an Actel Fusion device and a custom designed energy measurement circuit. The Fusion device measures the voltage and the current of the target device at a defined sampling rate. The energy measurement circuit is designed as a current integrator over fixed intervals using the switched-capacitor integrator technique to store energy information of the target device within Fusion’s sampling intervals. This circuit is designed to accommodate the low sampling rate of the Fusion device. Experimental results showed that the Fusion device allows the measurement of the energy of the target device at a minimum rate of 15 µs. The energy measurement circuit is implemented using the 65 nm CMOS technology. Simulation results showed that this circuit provides 91%~97% average energy measurement accuracy.

abstract: Utility scale solar energy is generated by photovoltaic (PV) cell arrays, which are often deployed in remote areas. A PV array monitoring system is considered where smart sensors are attached to the PV modules and transmit data to a monitoring station through wireless links. These smart monitoring devices may be used for fault detection and management of connection topologies. In this thesis, a compact hardware simulator of the smart PV array monitoring system is described. The voltage, current, irradiance, and temperature of each PV module are monitored and the status of each panel along with all data is transmitted to a mobile device. LabVIEW and Arduino board programs have been developed to display and visualize the monitoring data from all sensors. All data is saved on servers and mobile devices and desktops can easily access analytics from anywhere. Various PV array conditions including shading, faults, and loading are simulated and demonstrated. Additionally, Electrical mismatch between modules in a PV array due to partial shading causes energy losses beyond the shaded module, as unshaded modules are forced to operate away from their maximum power point in order to compensate for the shading. An irradiance estimation algorithm is presented for use in a mismatch mitigation system. Irradiance is estimated using measurements of module voltage, current, and back surface temperature. These estimates may be used to optimize an array’s electrical configuration and reduce the mismatch losses caused by partial shading. Propagation of error in the estimation is examined; it is found that accuracy is sufficient for use in the proposed mismatch mitigation application. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2016

Este trabalho descreve os requisitos para definição, implantação, manutenção e melhoria de sistemas de gestão de energia no ambiente industrial com um enfoque sistemático no que se refere às rotinas de melhoria contínua para eficiência energética. Para tanto, propôs-se a estruturação de uma plataforma automatizada visando o monitoramento, verificação e gerenciamento de recursos energéticos compatível com um sistema de gestão de energia normatizado, incluindo os requisitos de uso e consumo de energia, além do monitoramento, documentação, comunicação, melhores práticas de projeto, aquisição de equipamentos, sistemas, processos e recursos humanos envolvidos no desempenho energético. A estratégia de análise do uso da energia proposta neste trabalho baseou-se na metodologia de monitoramento e gestão de índices que consiste em uma abordagem sistemática na utilização de recursos energéticos objetivando alcançar o melhor resultado econômico através da gestão permanente do consumo de energia. Além disso, propôs-se a inclusão dessa metodologia como um procedimento na fase de planejamento da norma ISO50001, a qual estabelece os conceitos para a implantação de sistemas de gestão de energia. Visando integrar as ferramentas associadas a este cenário, esta plataforma contempla o uso de um sistema de supervisão associado a um aplicativo (Soft-PLC) que executa a aplicação de controle do uso de energia em um ambiente industrial com automação distribuída compatível com a norma IEC61131. O projeto do aplicativo de controle do uso de energia foi conduzido adotando-se diferentes linguagens de programação definidas na IEC para executar todos os procedimentos de medição, monitoração e gestão exigidos pelo sistema, incluindo análise comparativa com as “melhores práticas”, uso de tecnologias inovadoras, abordagem de produto e serviço, auditoria energética e conformidade com marcos regulatórios. Os resultados decorrentes da adoção de uma plataforma baseada em automação para o gerenciamento energético incluem elevada flexibilidade, adaptabilidade e usabilidade do sistema. Além disso, um projeto de automação neste cenário de plataforma aberta tende a apresentar menores custos de desenvolvimento e implantação. / This work describes the requirements for the definition, implementation, maintenance and improvement of energy management systems in the industrial environment with a systematic approach concerning continuous improvement routines for energy efficiency. For this purpose, it was proposed the establishment of a framework based on automation to implement monitoring, verification and management of energy resources compatible with a standardized energy management system, including requirements for energy use and consumption, in addition to monitoring, documentation, communication, project best practices, equipment acquisition, systems, processes and human resources involved in energy performance. The strategy of energy use analysis proposed in this work is based on the methodology of monitoring and targeting that consists of a systematic approach in the use of energy resources in order to achieve the best economic result through the permanent management of energy consumption. Furthermore, this work includes that system as a procedure in the planning phase of ISO50001 standard which establishes the concepts for energy management systems implementation. In order to aggregate all tools associated to this scenario, this paper proposes the use of a supervisory tool integrated to a real-time software (Soft-PLC) that runs the control application and a factory floor distributed system automation hardware in an IEC61131 compatible environment. The project of the control application of energy use was conducted using different programming languages defined in IEC to perform all the procedures of measurement, monitoring and management required by the system, including comparative analysis with the "best practices", use of innovative technologies, product and service approach, energy audit and compliance with regulatory milestones. The expected results of adopting an automation-based platform for energetic management include system flexibility, adaptability and usability. Besides, a project of automation in this scenario of open platform tends to introduce lower development and deployment costs.